Salts of keto aromatic acids



Patented May 14,1935

fIihi's mwention relaltes: to salts :of keto l-aro: matic acids-in which the metalxis presentinkra form in which it has aavalence of" thriee.or mor;e. Any metaihe element bwhich, f-ini'its trivalent. or higher form, is :sumci'ently :basic toiorma salt; of c or. of- :a mixture of. such acids fiorwofwoireior more :lceto aromatic acids in' admixture with" another acid may ce used Fprep'aniing the lsalts :of: the present "invention; Bifvalient salts of i'such smetals .as manganese, iron :a-ndweobatt iaretnot included the. scope of ,1 theuzprsent 1 application as these: form the i subject matteruof ionr co-pending application due results which is in most Serial No. 501,074

manganimgferric amdrcohalticrsalts. :ofiketo :aro matic acid substances, however, are included among, the otheriselltsof metals ofthigher, valen ce in the present application. c 7 lost iall'th ejketo aromatic acid saltsjwliich form subiicc'tmatter oi the present invenv ,n vs l e' fo b them ibemlg. fii'isohibl'e or ;;only slightly soluble ywater'falthough certaintgexceptions' may occur,. -notablythe ferric rsa-lts-of benzoyl benzoic acid.

pear to undergo a change indicating the possibility of an allotropic form,

cases readily soluble in the common organic solvents, giving a lacquer-likefilm on drying. In general they ex-' 'hibitno sharp meltingpoints, but at elevated temperatures become soft and more or v less plastic; further heating usually results in decomposition of the products.

At present the mostimportant commercial use of the salts of thepresent inventionappears to lie in the fieldofi plastics and coating compo- .sitions, where the ready solubility in organic solvents which-many of. them exhibit naturally -and most of them after. the heat treatment above referred to and where the characteristic which they all possess of forming hard and tough films on evaporation of such solvents makes them particularly useful. Another important advantage of these salts lies in the fact that they present a ready means for obtaining metals of the valence of three or higher in the form of a compound which is soluble in organic solvents a possibility that has heretofore existed very rarely in the case of solvents of low polarity and is not at all common even with such comparatively good solvents for inorganic substances as alcohol and the like.

The salts of the. presentinvention may be" prepared by reacting aqueous solutions of; the

.No Drawing. wflmilicatiom December episode q SeriaLNo; 501,073 :3 v

of even date-herewith; The

ben'zo yl. When heated to above 80 C. many of, them apand a gummy resi-" the netlresult is 'the same.

aa mpiascieaa by mesne as desired; metal -iic -ittm form of a compound in which-it 'exhibits az valence. such .the nitrate,

of three or ,more, :sulfate, :1chloride,; carbonate,

or'i'other :salt; with keto aromatic acids, either singly orwtin admixture-,1 or unlined-mixtures of keta arem t I e y with other, acids :such as sita eJ q iee h he a, resin acidsand the like, in case unmixed keto, aromatic acid-compound is] vnot desired. 'Inmost cases it is prefer; able .to carry out the. reaction "using the] ammoor alkali metal salts? or the 'or ganic'acids Whichi'can ,be readily prepared 'by' dissolvingfth'e free acid-"in a suitable olutionof (the alkali.

The keto acids have the; formula" naoo w'coon v .m "eii'IIferRT dbh TWP!d R romatic nuclei. Examples "er such compounds falling under the defini'tion' of ketoaromat c; fa j"are 'aceto-benzoic acid, 'loenzoyl .benzoyl'benzcicacid and the dike sih o hd fo fa' d isi si w ibn P nicks tweexflrqt h qfi en ie ei eh benioi'ci a Since the metals which areused to form the salts of the present invention are of a valence of three or higher, it is possible toform further series of compounds in addition to those resulting from the reaction of a single, metal compound with a single keto aromatic acid. For example, mixtures of the various keto aro- .matic acids or of their ammonium or alkali metal salts can be prepared and reacted with a single salt of the desired metal, or-the keto aromatic acid. may be so reacted in admixture with other acids or-salts such as 'stearic, lactic, resin acids, acid resins and they like. It is quite possible that in some cases only unstable compounds may result from the simultaneous reaction of difierent organic acid substances or even mixtures of the non-alkali forming metal salts of the acids may be obtained, but as the chief use of the products is in solution or within the confines of a resin of high molecular weight The invention is not limited to reaction products of a single organic acid compound with a single metal, but includes products obtained by the reaction of any metal compound in which the metal has a valence of three or more with mixtures of differv ent keto aromatic acids or with mixtures containing one or more ketoaromatic acids and 'an acid of another type.

At present the chief use of the keto aromatic acid" salts lies in the preparation of plastic as described in the prior applica- Example 1 I W Benzoyl benzoic acid is prepared mixing 200 parts of phthalic anhydride, 380 parts alumheating at this point for one hour, and refluxing The product is poured" into a solution of 280 parts of NazCOg'e'xcessfor an additional hour.

benzol removed by steam distillation, and .the free acid liberated with dilute hydrochloric acid.

The purified acid so obtained-is treated with sufficient dilute ammonia to form the ammon ium salt,afterwhich' the aluminum salt-is prepared by adding equivalent amounts of a solution of aluminum chloridef-The product {so obtained is separated on'afilter, washed, and dried; and aftersolution in organic solvents is suitable for the preparation of "an orange red lakewith. Aliz'arin brown dye; This lake can be used in the preparation of colored plastic and coating compositions as described in'our co-pending application Serial No. 503,855 filed December 20, 1930;

- Example i The chromic salt ofalphanaphthoylbenzoic acid is prepared by adding equivalentamountsof a solution of CrC13.6I-I2O to a solution'oi the ammonium salt of alphanaphthoylbenzoic acid, prepared in the usual manner. washedand dried and forms, after solution'in an :organic solvent, an excellent compound for the preparation of color lakes of sucli dyes: as

and heated at 50 C. during 2-3 hours.

product is poured cess benzol distilled v 'acidlib'erated and purified, and the ammonium.

What is claimed as new is:

The product is corresponding to the Anthracene brown, Alizarin Bordeaux R, Alizarin maroon and thelike.

Example 3.

Benzoylpropionic acid is prepared by the reaction of 140.5parts-by weight of benzol, 53.4 parts aluminum'chlorida and 20 parts of succinic anhydride, the reagents being brought into intimate admixture at temperatures below 15%;.

e into dilute ammonia, the exofi with steam, the free salt is again formed by the addition of equivalent amounts of dilute ammonium hydroxide solution.

; .IThe' product so, produced is treated with solutionsof ferric chloride, stannic chloride, cobaltic chloride or other soluble salts of trivalent metals to produce the corresponding salt of benzoylpropionic acid, which "can be dissolved in organic solvents and used'for the. preparing of films, with orv without plasticizers In the'ioregoing examples the preparation of keto: aromatic acid salts. of representative trivalent and tetravalent metals has been described, but it is to be understood that the invention is not limited to the specific'saltsproduced. n the contrary, salts of many other metals, such as antimony, gold, titanium, platinum, molybdenum, cerium, iridium, uranium and manganese can be prepared by similar methods and are included in the present invention.

.Salts of .ketoaromatic acids haVingtheifor- (R-{CO-R'COO) M in which R is an aromatic and R is an aliphatic radical, and M is any salt-forming metal having a valence of 3 or highenand is a number valence of the 'metal. LLOYD C. DANIELS. ALPHONS O. JAEGER. 

